Genital inspections bingo?
You dont have a issue about being naked in front of strangers of either sex. Some people do.
The problem is that up untill 5 min ago we developed rules to manage the multiple possible points of contact between humans and breaking them 'because I want to' was not accepted as a reason to change the rule.
Pulling out the chamber pot in the middle of dinner was practical but not respectful of your guest and a guest would have been rude to request it. Accidently chucking its content on your guests or strangers heads as you disposed of it out the window was known risk of this practical disposal. So rules can be changed.
Anyway human knows which sex they fall under.
The rules developed to safeguard one group against the other group.
Why is there any obligation on the person who has not broken the rule?
Why is it that the rule breaker gets an 'if I dont get caught It is OK to break the rules' pass?
As for where does it stop, why is that the question we as a society need to ask?
The individual can correctly sex themselves.
The individual knows they are breaking the rule.
Why is the onus on society to be forced into policing the individuals body?
If society agrees that the rule remains why shoild society not put a process in place to police the rule?
If a society can pass a law which allows the State to strip search an arrested person for shoplifting or being drunk in public why should a different standard apply for breaking the law around single sex spaces?
And FYI the society in question had a whole group of women who had to launch a political campaign on ' why a person should not be employed by the State and allowed to comit a sexual assault as part of the job description ' on a person who had already been assaulted.